This invention relates to an improved sealing and support arrangement for the camshaft of a cam brake system.
Cam brakes arc used to brake heavy vehicles such as trucks, by moving brake linings into contact with a brake drum upon rotation of a cam. The cam is typically in the form of an "S" shape. The cam rotates to force rollers radially outwardly, which then move the brake linings into contact with the drum. A camshaft, which rotates the cam, is rotated by an air brake actuator, typically through a connection with a slack adjuster. The camshaft must withstand very high forces as it is rotated to actuate the brake, and thus must be securely and properly mounted within its housing. In addition, lubrication of the camshaft to insure proper rotation is also necessary. In the prior art, seals and bearings have been provided between the camshaft, its housing and the slack adjuster; however, the seals and bearings have not always adequately mounted and sealed the camshaft. Rather, prior art camshafts have required frequent maintenance.
In addition, the connection between the slack adjuster and the camshaft has presented some difficulties. A large amount of rotational force is passed between the two members. Proper position and adequate sealing are also important at this connection, and yet sometimes difficult to achieve.